The present invention is related to railroad freight cars, and particularly to well cars intended to carry intermodal cargo containers in a container well which surrounds a lower portion of a cargo container.
Intermodal cargo containers, designed to be carried interchangeably on highway truck chassis, in containership holds, and on specially designed railroad cars, are constructed in several sizes, some of which are commonly used in international commerce. Until recently, most such containers have had a standard width of about 96 inches. Some intermodal cargo containers have more recently been built in a greater width of about 102 inches. Various lengths of cargo containers have long been available, and various railroad cars including container wells have been built to accommodate containers of different lengths interchangeably, although most have been built to carry containers no more than about 96 inches in width, since it is necessary for a railroad car to be narrow enough to fit within the available clearances along the track.
It is naturally desirable to be able to carry containers of different sizes in the container well of a railroad car, depending upon what containers are available to be carried, rather than having the railcar stand idle because of a mismatch of railcar and container sizes. Previously railcars have therefore been able to carry containers of different lengths, such as 20 feet, 40 feet, 45 feet, and 48 feet in length. Most containers are provided with strengthening and corner securing devices whose placement is based on the standard 40-foot container length, so that longitudinal placement of containers in the container well of a railcar is not generally a problem. However, the height of the side sills and the related depth of the container well are small enough in some railcars designed to carry containers of 102-inch width that there is room for a 96-inch-wide container to tip sideways and roll out of the container well, rotating about a longitudinal axis and pivoting about the top of the side sill of the car, unless provision is made to restrain the container against lateral movement.
An early attempt to restrain a container laterally, by providing a spacer structure in the side sill of a container car including a well, was disclosed in Pavlick, U.S. Pat. No. 4,648,764, which shows a spacer which can be placed between the side wall of a car and a container located within a container well. However, the spacer taught by Pavlick is apparently located near the bottom of a container carried in the well and would apparently not do anything to prevent the possibility of the container rolling from its intended place within the container well.
Gramse, et al., U.S. Pat. No. 4,754,709, provides a adjustable guide and spacer designed to be located at the top of a side sill of a container well car to take up the additional space available when a narrow container, e.g. 96 inches wide, is placed within a container well designed to be able to accept wider containers, e.g. 102-inch wide containers.
During the process of loading containers into the container wells of railway cars, a container crane operator attempts to align the container accurately with the well into which it is to be placed, but small errors in placement are nevertheless likely. It is therefore common to provide inclined guides affixed to the top of each side of the container well to center a container of a certain width laterally with respect to the well. However, when a car including a container well of a certain width is used to carry a narrower container than normal, a fixed guide of this sort would not be effective.
It is therefore desired to provide a guide to center containers with respect to the side walls of a container well, so that both wider containers and narrower containers will be centered within the container well during loading and will be retained in that location during carriage. However, there is ordinarily no need for such a guide to extend laterally very far outward when a standard container is being loaded into a well wide enough to accept wider containers. Provision of an unnecessarily large guide device merely adds undesirable weight to the car.
Ideally, when a container of standard width is to be loaded into a wider container well, a guide will have previously been placed on the inner side of the side sills of the well to ensure that the container will be placed centrally in the container well. Furthermore, a stabilizing device or spacer will have been placed between the container and the inner face of the side of the container well, so that the container will be prevented from tipping sideways. If a spacer has not been so placed, however, a spacer according to the prior art such as the Pavlick or Gramse, et al. patents mentioned above apparently could not be placed in the desired position between the container and the interior of the container well after a container has been loaded into the container well. As a result, the container would have to be removed from the container well during adjustment of the spacer and thereafter would have to be reloaded into the container well.
What is needed, then, is an adjustable device for guiding either a wider or a narrower container into a central location in a wider container well of a freight car, and then preventing the container, particularly a narrower container, from rolling out of the well. Such a device should not add excessive weight to the railcar, yet should be adequately sturdy to resist lateral movement of a container narrower than the container well, to prevent it from tipping. A container restraining spacer portion of the device should be movable into a position effective to prevent lateral movement of a container which has already been placed into the well, without requiring prior removal of the container to accomplish such adjustment.